The annual Muslim pilgrimage to the sacred city of Mecca that wrapped up last week became a death march for over 1,300 Hajj participants who died in temperatures that climbed above 124 degrees.

Saudi Arabia’s health minister Fahad Al-Jalajel, who on Sunday announced a death total of 1,301, blamed the fatalities on pilgrims “walking long distances under direct sunlight without adequate shelter or comfort.”

The 5-6 day odyssey of hiking and prayer drew almost 2 million pilgrims from around the world. Fatalities included a number of elderly people and those suffering from chronic diseases, A-Jalajel said. About  83% of the fatalities were among people who were not authorized to make the pilgrimage, he said.

“It’s only by God’s mercy that I survived, because it was incredibly hot,” Aisha Idris, a Nigerian pilgrim, told the BBC.

More than 650 of those who died were Egyptian; at least two were American.

Hajj is the fifth of pillar of Islam, and all Muslims are expected to make the pligrimage at least once in their lives. Maryland residents Alieu Dausy Wurie, 71, and wife Isatu Tejan Wurie, 65, spent $23,000 on an all-inclusive travel package through a tour company registered in the state.

“They saved their whole lives for this,” Saida Wurie told CNN.

Maryland couple’s death ruled ‘natural causes’

Wurie told CNN her parents were in Saudi Arabia when she learned via the family group chat that the tour company did not provide the proper transportation or credentials to be authorized for the pilgrimage. A man on their tour group contacted Saida Wurie to say her parents were missing on Mount Arafat after her father said that he could not continue.

Wurie said she was later contacted by U.S. Consulate officials in Jeddah saying they were notified by the Saudi Interior Ministry that her parents had died of “natural causes.” The State Department, contacted by USA TODAY, would say only that “we can confirm the deaths of multiple U.S. citizens in Saudi Arabia.  We offer our sincerest condolences to the families on their loss. We stand ready to provide all appropriate consular assistance.”

Egypt to prosecute tourism companies

Egyptian officials said the high number of deaths, most of them among unregistered pilgrims, stemmed from some companies that used a “personal visit visa (that) prevents its holders from entering Mecca” via official channels.

Prime Minister Moustafa Madbouly ordered the revocation of licenses for 16 tourism companies that provided packages for Hajj pilgrims who were not registered for the event. He also instructed that the officials of these companies be referred to prosecutors and the companies be fined to compensate the families of the deceased pilgrims.

Authorities in Jordan said they, too, had detained several travel agents who arranged unofficial travel of Muslim pilgrims.

Hajj heat deaths: 500 Egyptian pilgrims perish in 124-degree temps

Hajj has seen tragedy before

Catastrophic deaths at Hajj are not new. A stampede in 2015 killed more than 2,200 people, and another stampede in 1990 killed over 1,400 people. Four years later a stampede killed 270 people. A tent fire in 1997 killed 347. A protest turned violent in 1998, leading to the deaths of 400 pilgrims. In 2009, 77 pilgrims were killed in floods.

Contributing: Reuters

This article originally appeared on USA TODAY: Hajj participants die in Muslim pilgrimage to Mecca in 124 degrees